Conventionally, there has been known a device configured to release a lock by means of a face recognition.
For example, in one authentication system, a mobile phone includes a storage unit configured to store in advance authentication information related to a face image of a user, a housing state monitoring unit configured to detect a predetermined state of the mobile phone, an application monitoring unit, and an acquiring unit configured to acquire a face image of a user, without notifying a user, by using a detection of the predetermined state as a trigger. This mobile phone further includes a determination unit configured to compare an obtained face image and the authentication information stored in the storage unit and determine whether or not the face image and the authentication information match, and a function control unit configured to release a lock of a predetermined application prior to the determination performed by the determination unit, maintain the released state when determined that the face image and the authentication information match, and otherwise lock a predetermined function.